But isn't Yakone kind of a swarthy gentleman? And aren't Amon's hands kind of pale? From that very short finale preview, Amon really did strike a pose similar to that of a bloodbemder and they chose to show this right after showing a clip of Mako being bloodbent, but something tells me Amon isn't Yakone either.
I think it's more likely that Amon is someone who has yet to be introduced and has gained the ability to absorb others' bending abilities instead if taking them away. I think he wants to be the only bender and bring his own twisted definition of "balance" to the world. Also I seriously doubt he's all burnt up.